There are a large number of analysis instruments and equipment available. Analysis of biological samples continues to be extensively done on a macro scale and frequently requires a large number of process steps.
One of the most extensively used analysis techniques within the life sciences laboratory is gel bath based electrophoresis. This process enables separation of a complex mixture of charged molecules, such as nucleic acids or proteins, according to their electro-phoretic mobility. Following this method, the relative molecular weight and amounts of the constituent molecules can be determined. However, this well established technique is time consuming, labour intensive and requires significant amounts of bench space. Sample preparation, sample analysis and sample clean-up all involve wet chemistry in which some of the reagents used (e.g. ethidium bromide) are toxic, and require specialised handling and disposal methods.
A common operating configuration for the electrophoresis and analysis of DNA fragments using a slab gel includes:    an ultra pure demineralised water supply;    bulk supply bottles of buffer reagent;    chemical stains or dyes;    gel powder;    laboratory glassware for gel preparation;    a heating and stirring device for gel preparation (mix powder with buffer);    a gel tank and all its accessory parts;    an electrical power supply unit;    a sample loading pipette;    a light box on to which the processed gel is transferred such that the fluorochromes in the gel can be activated; and    a gel camera, the most basic arrangement of which would be an instant camera attached to a metal hood which can be fitted in a light tight arrangement to the light box.
Available improvements to this traditional process are: pre-cast gels that “drop-in” to a standard gel tank, such as those provided by the Novex® brand of Invitrogen Corporation, or the ReadyAgarose® brand of Bio-Rad Laboratories. However, these gels still require “wet chemistry” handling procedures and remain time and labour intensive.
Other improvements include:    rigid gel plates into which the user can cast a gel matrix;    gel tanks that can simultaneously process multiple pre-cast or home made gels but which require much handling and wet chemistry preparation;    pre-cast gels that do not require a gel tank or buffers such as the “E-Gel™” system provided by Invitrogen Corporation (ref U.S. Pat. Nos. 5,582,702 and 5,865,924).
The “E-Gel™” system still incurs the inconvenience and handling overheads of manual sample loading and the use of a separate image capture station for analysis
One of the commonest nucleic acid stainers employed during electrophoretic separation and imaging is ethidium bromide. This stainer has the disadvantage of requiring an Ultra-Violet (UV) light source to trigger the fluorescence upon which electrophoretic imaging relies. A requirement of UV imaging systems is to protect the user from UV radiation using either fully enclosed shielded light boxes or using goggles within a dark room.
An arrangement in common use is to use one of a number of commercially available gel imaging systems. A gel is processed in the traditional manner in a gel bath, but it is then manually transferred from the gel bath to the top surface of a separate light box contained within a light tight enclosure that contains a digital camera connected externally by cable to a viewer or an image printing device. Examples of available systems are manufactured by UVP Incorporated (brand name GelDoc-It), Bio-Rad Laboratories (brand name Gel Doc) or Synoptics Limited (brand name Syngene).
A similar solution is to use a walk-in dark room which hosts a UV light box and a camera. However, systems including these imaging techniques, still require significant levels of reagent preparation, careful manual sample loading and the set up and use of multiple pieces of apparatus.
Examples of systems which automate the traditional slab gel process are Helena Bio-Sciences, U.S. Pat. Nos. 4,954,237 and 5,147,522. These systems are relatively bulky and their automation process still involves the preparation, processing and automated handling of a traditional wet chemistry slab gel.
Fully automated electrophoresis devices that use capillary electrophoresis (as distinct from slab gel electrophoresis) address some of the issues involved in gel bath electrophoresis. However, these types of apparatus are large and expensive and require specially trained operators. They are normally used to carry out high resolution separation (down to a single base pair) of nucleic acids or high throughput single nucleotide polymorphism (SNP) analysis where automation is essential. An example of this type of system is the Applied Biosystems Inc Prism 3100 Genetic Analyser. The cost and complexity of these systems usually prohibits their use in small laboratories.
Microfluidic devices are beginning to be used in molecular biology. The Agilent Bio-analyser 2100 is a bench top device using the Caliper “Labchip®”. This system exploits microfluidic techniques to achieve rapid separation. The system is however not fully automated and samples are processed in a serial (as opposed to parallel) fashion.
The challenges for systems that seek to replace slab gel electrophoresis and aim to achieve significant reductions in separation time are:    to eliminate the need for reagent preparation (gel, buffer, electrolyte) other than those associated with test sample preparation.